U.S. Pat. No. 6,343,495 discloses a portable device for local shot peening of a part to introduce compressive stress or to modify its surface quality.
United States application US 2002-0042978, French patent FR-A-2 815 280 and US 2006-0021410 disclose units in which the part to be treated is at least partly introduced into the unit.
Such units are suitable when treating component parts of a machine during fabrication thereof or when maintaining it after dismantling the machine completely.